Sound-box



L. L. HUGHES.

SOUND BOX.

APPLICATION FILED MAR.2a.192I.

, Patented D00. 6,

UNITED STATES PATENT OFFICE.

LEO LHULIER HUGHES, 0F WASHINGTON, DISTRICT Ol" COLUMBIA.

SOUND-BOX.

Specification of Letters Patent.

Patented Dec. 6, 1921.

Application filed March 28, 1921. Serial No. 456,315.

have invented certain new and useful Improvements in Sound-Boxes, of which the following is a speciiication.

My invention relates to phonographs, and has for its object to provide means for improving the quality of the sound reproduced by such instruments.

Other and further objects will be in part described and in part obvious as the specication is proceeded with.

In the drawings:

Figure 1 is a side elevation of the reproducing mechanism of a phonograph equipped with my invention;

Fig. 2 is a front view showing the construction of the tone arm support;

Fig. 3 is a section on the line 3-3 of Fig. 2;

Fig. 4 is a section on the line H of Fig. 2; and

Fig. 5 is a section on the line 5 5 of Fig. 2.

Referring to the drawings and the illustrative embodiment of the invention therein disclosed, 5 denotes the sound reproducingmechanism comprising the sound box 6 having the diaphragm 7 of any suitable material clamped thereto by means of the metal ring S. A flexible stylus bar support 9 preferably of spring steel is secured to the upper outer face of the ring 8 of the sound box in the following manner.

Mounted on the upper end of the ring 8 of the sound box at the front thereof is a plate 10 formed with oppositely disposed ears 30 adapted to register with corresponding ears 31 projecting from the inner and outer edge of the ring 8. Any suitable fastening means such as screws 12 clamp the plate 10 to the ring 8. Arranged on each side of the plate 10 are brackets 11 having upstandinff apertured lugs 13 for a purpose presently to be described. These brackets are secured to the sound box by means of screws 14.

The upper end of the stylus bar support 9 is secured to the plate 10 by means of rivets 15, suitable insulation 16 being inserted between the plate and tone arm. The plate 10 is formed with a recess 17 adapted to receive the correspondingly shaped rib 18 formed on the face of the ring 8. The stylus bar support is also secured between the upstanding lugs 13 by means of oppositelv disposed pivot screws 197 the ends of which seat in recesses 2O formed in the side edges of the stylus bar-support. The bifurcations 21 of .the stylus bar support are connected at their lower ends by a cross plate 22 to which is suitably secured the carrier 23 for the tracking point or stylus 33, a suitable packing 32 being employed at the point of connection. i

A stylus bar 24 connects the upper end of the stylus carrier with the diaphragm 7 for an obvious purpose.

By loosening the screws 19 and tightening one or the other of the screws 12 it is possible to rock the plate 10 and stylus bar support on the rib 18 as a fulcrum and thereby adjust the diaphragm 7 to proper tension by exerting either an inward stress oroutward pull on the diaphragm through the stylus-bar 24.

In the operation of my device the vibrations are conducted directly from the stylus through the stylus bar 24 to the diaphragm, but any vibrations which reach the stylus bar support will belost therein by virtue o f the fact that the support is of much greater length and area than that of the tone arm. In other Words these escaping vibrations will not be returned downwardly through the support in any consequent communication brations to the diaphragm.

In prior devices the stylus support is connected directly to the lower end of the sound box and consequently the vibrations to a large extent escape into the sound box with objectionable results.

Having thus described my invention, what I claim is:

In combination with a sound box havingv of conflicting viappreciable degree with a diaphragm, a stylus bar support pivotally secured at one end to the upper end of the sound box, the other end of said support being free, a stylus carrier and a stylus bar carried by the free end of said support, and means for rocking said support on its pivot.

In testimony whereof I aix my signature.

Lno LHULIER HUGHEs. 

